Vehicular seat, watercraft seat, method for making vehicular seat, and method for making watercraft seat

ABSTRACT

A vehicular seat, a watercraft seat, a method for making the vehicular seat, and a method for making the watercraft seat that can achieve a favorable riding comfort, reduce the number of work processes involved, and reduce a manufacturing cost even by foaming a first cushion member of urethane on a second cushion member of a thermoplastic elastomer to make an integrated assembly of the first cushion member of urethane and the second cushion member. A vehicular seat includes a first cushion member formed of urethane and covered with a seat skin and a second cushion member formed of a thermoplastic elastomer and disposed between the first cushion member and a bottom plate. A covering sheet is disposed between the first cushion member and the second cushion member.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 USC 119 to JapanesePatent Application No. 2010-042256 filed on Feb. 26, 2010 the entirecontents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicular seat, a watercraft seat, amethod for making the vehicular seat, and a method for making thewatercraft seat.

2. Description of Background Art

A vehicular seat and watercraft seat is known that includes a firstcushion member formed of urethane and covered with a seat skin and asecond cushion member formed of a thermoplastic elastomer and disposedbetween the first cushion member and a bottom plate. See, for example,Japanese Patent Laid-open No. 2007-175482.

In the vehicular seat and the watercraft seat disclosed in JapanesePatent Laid-open No. 2007-175482, however, the first cushion member andthe second cushion member are formed separately from each other andthereafter bonded together. This involves a large number of workprocesses, resulting in an increased manufacturing cost. To reduce thenumber of work processes, a one-piece molding process may be possible,in which the first cushion member of urethane is foamed on the secondcushion member of thermoplastic elastomer. In this case, however, afoaming pressure causes the first cushion member to bite into and befused with the second cushion member, resulting in degraded ridingcomfort.

SUMMARY AND OBJECTS OF THE INVENTION

The present invention has been made in view of the foregoing situationsand it is an object of an embodiment of the present invention to providea vehicular seat, a watercraft seat, a method for making the vehicularseat, and a method for making the watercraft seat that can achieve afavorable riding comfort, reduce the number of work processes involved,and reduce the manufacturing cost even by foaming a first cushion memberof urethane on a second cushion member of a thermoplastic elastomer tomake an integrated assembly of the first cushion member of urethane andthe second cushion member.

To achieve the foregoing object, an embodiment of the present inventionprovides a vehicular seat that includes a first cushion member formed ofurethane, the first cushion member being covered with a seat skin; asecond cushion member formed of a thermoplastic elastomer, the secondcushion member being disposed between the first cushion member and abottom plate; and a covering sheet disposed between the first cushionmember and the second cushion member.

According to an embodiment of the present invention, the covering sheetis disposed on the second cushion member on a side thereof adjacent thefirst cushion member, and not on an entire surface or part of a sidethereof adjacent the bottom plate.

According to an embodiment of the present invention, the bottom platehas a rib disposed on an upper surface thereof, the rib extending towarda side of the second cushion member.

According to an embodiment of the present invention, a watercraft seatis provided that includes a first cushion member formed of urethane, thefirst cushion member being covered with a seat skin; a second cushionmember formed of a thermoplastic elastomer, the second cushion memberbeing disposed between the first cushion member and a bottom plate; anda covering sheet disposed between the first cushion member and thesecond cushion member.

According to an embodiment of the present invention, the covering sheetis disposed on the second cushion member on a side thereof adjacent thefirst cushion member, and not on an entire surface or part of a sidethereof adjacent the bottom plate.

According to an embodiment of the present invention, the bottom platehas a rib disposed on an upper surface thereof, the rib extending towarda side of the second cushion member.

According to an embodiment of the present invention, a method for makinga vehicular seat is provided wherein the vehicular seat includes a firstcushion member formed of urethane, the first cushion member beingcovered with a seat skin; a second cushion member formed of athermoplastic elastomer, the second cushion member being disposedbetween the first cushion member and a bottom plate; and a coveringsheet disposed between the first cushion member and the second cushionmember. The method includes the steps of forming the second cushionmember; affixing the covering sheet generally to the second cushionmember excluding part thereof; setting the second cushion member, towhich the covering sheet is affixed, into a first mold; loading aurethane material into a second mold; closing the first mold and thesecond mold; foaming the urethane material to thereby integrally formthe first cushion member on a surface of the covering sheet affixed tothe second cushion member; removing an integrated assembly of the firstcushion member, the second cushion member, and the covering sheet fromthe first mold and the second mold; and mounting the bottom plate on alower surface of the integrated assembly of the first cushion member,the second cushion member, and the covering sheet, covering a surface ofthe first cushion member with the seat skin, and mounting the seat skinon the bottom plate.

According to an embodiment of the present invention, a method isprovided for making a watercraft seat, the watercraft seat includes afirst cushion member formed of urethane, the first cushion member beingcovered with a seat skin; a second cushion member formed of athermoplastic elastomer, the second cushion member being disposedbetween the first cushion member and a bottom plate; and a coveringsheet disposed between the first cushion member and the second cushionmember. The method includes the steps of forming the second cushionmember; affixing the covering sheet generally to the second cushionmember excluding part thereof; setting the second cushion member, towhich the covering sheet is affixed, into a first mold; loading aurethane material into a second mold; closing the first mold and thesecond mold; foaming the urethane material to thereby integrally formthe first cushion member on a surface of the covering sheet affixed tothe second cushion member; removing an integrated assembly of the firstcushion member, the second cushion member, and the covering sheet fromthe first mold and the second mold; and mounting the bottom plate on alower surface of the integrated assembly of the first cushion member,the second cushion member, and the covering sheet, covering a surface ofthe first cushion member with the seat skin, and mounting the seat skinon the bottom plate.

According to an embodiment of the present invention, the covering sheetis disposed between the first cushion member and the second cushionmember. Even if the first cushion member of urethane is foamed to beintegrally formed on the second cushion member of the thermoplasticelastomer, the foamed first cushion member is blocked by the coveringsheet. This eliminates the likelihood that the first cushion member andthe second cushion member will be fused together, so that favorableriding comfort of the vehicular seat can be achieved. In addition, thefirst cushion member can be foamed to be integrated with the secondcushion member. This reduces the number of work processes involved, sothat a manufacturing cost of the vehicular seat can be reduced.

According to an embodiment of the present invention, the covering sheetis disposed on the side of the second cushion member adjacent the firstcushion member and not on the entire surface or part of the side of thesecond cushion member adjacent the bottom plate. Air inside the secondcushion member can therefore be aspirated on the side of the bottomplate according to movement of the occupant, so that favorable ridingcomfort of the vehicular seat can be achieved.

According to an embodiment of the present invention, the rib extendingtoward the side of the second cushion member is disposed on the uppersurface of the bottom plate. The second cushion member can therefore beeffectively bled of air according to the movement of the occupant, sothat favorable riding comfort of the vehicular seat can be achieved.

According to an embodiment of the present invention, the covering sheetis disposed between the first cushion member and the second cushionmember. Even if the first cushion member of urethane is foamed to beintegrally formed on the second cushion member of the thermoplasticelastomer, the foamed first cushion member is blocked by the coveringsheet. This eliminates the likelihood that the first cushion member andthe second cushion member will be fused together, so that favorableriding comfort of the watercraft seat can be achieved. In addition, thefirst cushion member can be foamed to be integrated with the secondcushion member. This reduces the number of work processes involved, sothat a manufacturing cost of the watercraft seat can be reduced.

According to an embodiment of the present invention, the covering sheetis disposed on the side of the second cushion member adjacent the firstcushion member and not on the entire surface or part of the side of thesecond cushion member adjacent the bottom plate. Air inside the secondcushion member can therefore be aspirated on the side of the bottomplate according to movement of the occupant, so that favorable ridingcomfort of the watercraft seat can be achieved.

According to an embodiment of the present invention, the rib extendingtoward the side of the second cushion member is disposed on the uppersurface of the bottom plate. The second cushion member can therefore beeffectively bled of air according to the movement of the occupant, sothat favorable riding comfort of the watercraft seat can be achieved.

According to an embodiment of the present invention, the method includesthe steps of forming the second cushion member; affixing the coveringsheet generally to the second cushion member excluding part thereof;setting the second cushion member, to which the covering sheet isaffixed, into the first mold; loading the urethane material into thesecond mold; closing the first mold and the second mold; foaming theurethane material to thereby integrally form the first cushion member ona surface of the covering sheet affixed to the second cushion member;removing the integrated assembly of the first cushion member, the secondcushion member, and the covering sheet from the first mold and thesecond mold; and mounting the bottom plate on a lower surface of theintegrated assembly of the first cushion member, the second cushionmember, and the covering sheet, covering a surface of the first cushionmember with the seat skin, and mounting the seat skin on the bottomplate. The vehicular seat having the first and second cushion membersintegrated together can therefore be easily obtained by foaming theurethane material.

According to an embodiment of the present invention, the method includesthe steps of forming the second cushion member; affixing the coveringsheet generally to the second cushion member excluding part thereof;setting the second cushion member, to which the covering sheet isaffixed, into the first mold; loading the urethane material into thesecond mold; closing the first mold and the second mold; foaming theurethane material to thereby integrally form the first cushion member ona surface of the covering sheet affixed to the second cushion member;removing the integrated assembly of the first cushion member, the secondcushion member, and the covering sheet from the first mold and thesecond mold; and mounting the bottom plate on a lower surface of theintegrated assembly of the first cushion member, the second cushionmember, and the covering sheet, covering a surface of the first cushionmember with the seat skin, and mounting the seat skin on the bottomplate. The watercraft seat having the first and second cushion membersintegrated together can therefore be easily obtained by foaming theurethane material.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention, and wherein:

FIG. 1 is a left side elevational view for illustrating a motorcyclemounted with a vehicular seat according to a first embodiment of thepresent invention;

FIG. 2 is a partly cutaway perspective view showing the vehicular seatshown in FIG. 1;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a cross-sectional view for illustrating a vehicular seataccording to a second embodiment of the present invention;

FIG. 5 is a cross-sectional view for illustrating a vehicular seataccording to a third embodiment of the present invention;

FIG. 6 is a partly cutaway perspective view showing a vehicular seat fora four-wheel vehicle using a second cushion member according to thesecond embodiment of the present invention;

FIG. 7 is a partly cutaway perspective view showing a watercraft seatfor a saddle riding type watercraft using a second cushion memberaccording to the first embodiment of the present invention;

FIGS. 8( a) to 8(d) are views for illustrating processes formanufacturing the vehicular seat according to the second embodiment ofthe present invention; and

FIGS. 9( a) to 9(d) are views for illustrating processes that followthose shown in FIGS. 8( a) to 8(d) for manufacturing the vehicular seat.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A vehicular seat according to a first embodiment of the presentinvention will be described below with reference to FIGS. 1 to 3. Thedrawings should be viewed in the direction of reference numerals.Throughout the descriptions given hereunder, expressions indicatingdirections including front and rear, right and left, and upper and lowermean the same directions as those as viewed from an occupant. In thedrawings, an arrow Fr indicates forward of the vehicle, an arrow Lindicates leftward of the vehicle, an arrow R indicates rightward of thevehicle, an arrow U indicates upward of the vehicle, and an arrow Dindicates downward of the vehicle.

A motorcycle 1 mounted with the vehicular seat according to the firstembodiment of the present invention will be first described. Referringto FIG. 1, the motorcycle 1 includes a vehicle body frame 2, a pair ofleft and right front forks 3, a steering handlebar 4, a front wheel 5, arear fork (swing arm) 6, a rear wheel 7, an engine 8, a fuel tank 9, avehicular seat 10, a rider's step 12, a passenger's step 13, side trunks14, and a cowling 15. More specifically, the front forks 3 are rotatablysupported at a front end portion of the vehicle body frame 2. Thehandlebar 4 is attached on an upper end portion of the front forks 3.The front wheel 5 is rotatably supported by the front forks 3. The rearfork 6 is swingably supported on the vehicle body frame 2. The rearwheel 7 is rotatably supported at a rear end portion of the rear fork 6.The engine 8 is supported on the vehicle body frame 2. The fuel tank 9is disposed at an upper portion of the vehicle body frame 2. Thevehicular seat 10 is disposed rearwardly of the fuel tank 9, including arider's seat 10 a and a pillion 10 b. The side trunks 14 are mounted onboth left and right sides of a vehicle body at rear portions thereof.The cowling 15 generally covers the vehicle body.

Exhaust pipes 8A are connected to a cylinder portion of the engine 8.Each of the exhaust pipes 8A extends downwardly and, at a positiondownward of the engine 8, bends before being connected to a muffler 8Bdisposed rearwardly of the engine 8.

The cowling 15 includes a front cowl 17 and a rear cowl 18. Morespecifically, the front cowl 17 covers a front portion of the vehiclebody and has an upper end portion extending along a main frame 16 of thevehicle body frame 2. The rear cowl 18 covers a lower portion of thevehicular seat 10, more specifically, a rear portion of the vehiclebody. The front cowl 17 includes an upper cowl 17 a disposed at a frontend of the vehicle body, a middle cowl 17 b for covering a side portionof the engine 8, and an under cowl 17 c for covering a lower portion ofthe engine 8 (lower portion of the exhaust pipes 8A).

In FIG. 1, a windshield 21 is provided together with a headlight 22, aside mirror 23, a front flasher 24, a rear grip 25, a front fender 26, arear fender 27, and a stand 28.

Referring to FIGS. 2 and 3, the vehicular seat 10 includes a firstcushion member 41, a second cushion member 42, and a covering sheet 44.More specifically, the first cushion member 41 formed of urethane iscovered with a seat skin 40. The second cushion member 42 formed of athermoplastic elastomer is disposed between the first cushion member 41and a bottom plate 43. The covering sheet 44 is disposed between thefirst cushion member 41 and the second cushion member 42. Note that, inthe first embodiment of the present invention, the second cushion member42 is disposed on the side of the rider's seat; nonetheless, the secondcushion member 42 may also be disposed on the side of the pillion 10 b.In FIG. 2, the first cushion member 41 is omitted for ease ofunderstanding of a structure of the vehicular seat 10.

The bottom plate 43 is a sheet-like member formed of a synthetic resin.Referring to FIG. 3, the bottom plate 43 has a recessed portion 45formed at a central portion thereof, in which the second cushion member42 is fitted. The recessed portion 45 has a curved portion 46 formed oneach of both end portions in a vehicle width direction. The curvedportion 46 protrudes upwardly and is formed continuously. The bottomplate 43 also has a seat skin mounting portion 47 formed continuously oneach of outer end portions in the vehicle width direction of the curvedportions 46. The seat skin mounting portion 47 has a substantiallyJ-shaped cross section. The bottom plate 43 further has a protrudingportion 48 formed continuously at a central portion of a bottom of therecessed portion 45. The protruding portion 48 supports a lower surfaceof the second cushion member 42 and enhances stiffness of the bottomplate 43. A plurality of ribs 49 (a total of 12 on the left and rightsides shown in FIG. 3) is formed on an upper surface of the bottom ofthe recessed portion 45. The ribs extend toward the side of the secondcushion member 42 to support the lower surface of the second cushionmember 42 to enhance the stiffness of the bottom plate 43.

The second cushion member 42 is formed by cutting a block-likethermoplastic elastomer base material. Referring to FIG. 3, the secondcushion member 42 is formed into a shape having a rectangular crosssection and fitted in the recessed portion 45 of the bottom plate 43.According to the first embodiment of the present invention, it ispossible to make the occupant feel less corners of the second cushionmember 42 when seated by adjusting a thickness of the first cushionmember 41 and that of the covering sheet 44. Thus, the vehicular seat 10is thereby allowed to exhibit a uniform feel. The second cushion member42 is a thermoplastic elastomer striate body of an isotropic gel-likeviscoelastic body type that is coupled three-dimensionally into anet-like thermoplastic elastomer.

Referring to FIG. 3, the covering sheet 44 is affixed to a surface ofthe second cushion member 42 on the side adjacent the first cushionmember 41. The covering sheet 44 is not affixed to part of a surface ofthe second cushion member 42 on the side of the bottom plate 43. Morespecifically, the covering sheet 44 is affixed to an upper surface, sidesurfaces, and part of a bottom surface of the second cushion member 42.

The first cushion member 41 is formed integrally on a surface of thecovering sheet 44 affixed to the second cushion member 42 by foaming aurethane material in molds 81, 82 to be described later. This causes thecovering sheet 44 to be in tight contact with the first cushion member41 by a foaming pressure, facilitating clearance control.

As described heretofore, in the vehicular seat 10 according to the firstembodiment of the present invention, the covering sheet 44 is disposedbetween the first cushion member 41 and the second cushion member 42.Even if the first cushion member 41 of urethane is foamed to beintegrally formed on the second cushion member 42 of the thermoplasticelastomer, the foamed first cushion member 41 is blocked by the coveringsheet 44. This eliminates the likelihood that the first cushion member41 and the second cushion member 42 will be fused together, so that afavorable riding comfort of the vehicular seat 10 can be achieved. Inaddition, the first cushion member 41 can be foamed to be integratedwith the second cushion member 42. This reduces the number of workprocesses involved, so that a manufacturing cost of the vehicular seat10 can be reduced.

In the vehicular seat 10 according to the first embodiment of thepresent invention, the covering sheet 44 is affixed to a side of thesecond cushion member 42 adjacent the first cushion member 41 and is notto part of a side of the second cushion member 42 adjacent the bottomplate 43. Air inside the second cushion member 42 can therefore beaspirated on the side of the bottom plate 43 according to movement ofthe occupant, so that favorable riding comfort of the vehicular seat 10can be achieved.

In addition, in the vehicular seat 10 according to the first embodimentof the present invention, the ribs extending toward the side of thesecond cushion member 42 are disposed on the upper surface of the bottomplate 43. The second cushion member 42 can therefore be effectively bledof air according to the movement of the occupant, so that a favorableriding comfort of the vehicular seat 10 can be achieved.

In addition, in the vehicular seat 10 according to the first embodimentof the present invention, the second cushion member 42 is formed bycutting operations into a shape having the rectangular cross section.This eliminates the need for forming an obliquely cut surface 52 athrough cutting operations as in a second cushion member 52 of a secondembodiment of the present invention to be described later. As a result,the manufacturing cost of the vehicular seat 10 can be further reduced.

A vehicular seat according to a second embodiment of the presentinvention will be described below with reference to FIG. 4. Like orcorresponding parts are identified by the same reference numerals asthose used for the first embodiment of the present invention anddescriptions for those parts will be omitted or simplified.

Referring to FIG. 4, a vehicular seat 10 according to the secondembodiment of the present invention includes a first cushion member 41,a second cushion member 52, and a covering sheet 44. More specifically,the first cushion member 41 formed of urethane is covered with a seatskin 40. The second cushion member 52 formed of a thermoplasticelastomer is disposed between the first cushion member 41 and a bottomplate 43. The covering sheet 44 is disposed between the first cushionmember 41 and the second cushion member 52.

The second cushion member 52 is formed by cutting a block-likethermoplastic elastomer base material. Referring to FIG. 4, the secondcushion member 52 has a straight-line obliquely cut surface 52 a on eachside of an upper portion of outer end portions in the vehicle widthdirection thereof. The obliquely cut surface 52 a is formed such thatthe second cushion member 52 has a thickness that gradually decreasestoward the outside in the vehicle width direction.

As shown in FIG. 4, the covering sheet 44 is affixed to an uppersurface, the obliquely cut surfaces 52 a, side surfaces, and part of abottom surface of the second cushion member 52.

As described above, in the vehicular seat 10 according to the secondembodiment of the present invention, the second cushion member 52 isformed to have the obliquely cut surfaces 52 a through cuttingoperations. This eliminates the need for forming a protruding portion 62b and an arcuate surface 62 c by thermal forming as in a second cushionmember 62 of a third embodiment of the present invention to be describedlater. As a result, the manufacturing cost of the vehicular seat 10 canbe reduced.

In addition, in the vehicular seat 10 according to the second embodimentof the present invention, the second cushion member 52 has the obliquelycut surfaces 52 a formed at the upper portions on the outer end portionsin the vehicle width direction thereof. This allows an entire seatsurface of the vehicular seat 10 to exhibit a uniform feel duringseating.

Other arrangements and effects are the same as those of the firstembodiment of the present invention.

A vehicular seat according to a third embodiment of the presentinvention will be described below with reference to FIG. 5. Like orcorresponding parts are identified by the same reference numerals asthose used for the first embodiment of the present invention anddescriptions for those parts will be omitted or simplified.

Referring to FIG. 5, a vehicular seat 10 according to the thirdembodiment of the present invention includes a first cushion member 41,a second cushion member 62, and a covering sheet 44. More specifically,the first cushion member 41 formed of urethane is covered with a seatskin 40. The second cushion member 62 formed of a thermoplasticelastomer is disposed between the first cushion member 41 and a bottomplate 43. The covering sheet 44 is disposed between the first cushionmember 41 and the second cushion member 52.

The second cushion member 62 is formed by thermally forming a block-likethermoplastic elastomer base material. Referring to FIG. 5, the secondcushion member 62 has a main unit portion 62 a and protruding portions62 b. More specifically, the main unit portion 62 a is fitted into arecessed portion 45 in the bottom plate 43. Each of the protrudingportions 62 b protrudes outwardly from an outer end surface in thevehicle width direction of the main unit portion 62 a and is placed on acurved portion 46 of the bottom plate 43. In addition, an arcuatesurface 62 c is formed at an upper corner of each of the protrudingportions 62 b.

In addition, referring to FIG. 5, the covering sheet 44 is affixed to anupper surface of the main unit portion 62 a, upper surfaces, sidesurfaces, and bottom surfaces of the protruding portions 62 b, and sidesurfaces of the main unit portion 62 a of the second cushion member 62.

As described above, in the vehicular seat 10 according to the thirdembodiment of the present invention, the second cushion member 62includes the main unit portion 62 a and the protruding portions 62 bthat protrude outwardly from the upper portions of the outer endsurfaces in the vehicle width direction of the main unit portion 62 a.Each of the protruding portions 62 b includes the arcuate surface 62 cformed at each of the upper corners of the protruding portions 62 b.This allows both sides of the vehicular seat 10 to exhibit a uniformfeel during seating. Thus, the riding comfort of the vehicular seat 10can be further enhanced.

Other arrangements and effects are the same as those of the firstembodiment of the present invention.

The present invention has been described with particularity relative tothe detailed description of the exemplary preferred first through thirdembodiments, in which the present invention is applied to the vehicularseat 10 of the motorcycle 1. The present invention may still be appliedto a vehicular seat 71 of a four-wheeled vehicle as shown in FIG. 6 or awatercraft seat 72 of a saddle riding type watercraft as shown in FIG.7. In FIG. 6, the second cushion member 52 of the second embodiment ofthe present invention is used in the vehicular seat 71 of thefour-wheeled vehicle. The second cushion member 42 or 62 of the first orthird embodiment of the present invention may instead be used. In FIG.7, the second cushion member 42 of the first embodiment of the presentinvention is used in the watercraft seat 72 of the saddle riding typewatercraft. The second cushion member 52 or 62 of the second or thirdembodiment of the present invention may instead be used.

A method for making the vehicular seat or the watercraft seat accordingto an embodiment of the present invention will be described below withreference to FIGS. 8( a) to 8(d) and 9(a) to 9(d). In the descriptionsthat follow, the vehicular seat 10 according to the second embodiment ofthe present invention will be used as an example.

The method for making the vehicular seat 10 includes the steps of:forming the second cushion member 52 of the thermoplastic elastomer of anet-like structure by cutting (see FIG. 8( a)); affixing the coveringsheet 44 generally to the second cushion member 52 excluding part of thelower surface of the second cushion member 52 (see FIG. 8( b)); settingthe second cushion member 52, to which the covering sheet 44 is affixed,into a recessed portion 81 a formed in a lower surface of an upper mold(a first mold) 81 (see FIG. 8( c)); loading a urethane material 83 intoa recessed portion 82 b formed in an upper surface of a lower mold (asecond mold) 82 (see FIG. 8( d)); closing the upper mold 81 and thelower mold 82 (see FIG. 9( a)); foaming the urethane material 83 in acavity 84 formed between the upper mold 81 and the lower mold 82 andintegrally forming the first cushion member 41 on the surface of thecovering sheet 44 affixed to the second cushion member 52 (see FIG. 9(b)); removing an integrated assembly of the first cushion member 41, thesecond cushion member 52, and the covering sheet 44 from the upper mold81 and the lower mold 82 (see FIG. 9( c)); and mounting the bottom plate43 on a lower surface of the integrated assembly of the first cushionmember 41, the second cushion member 52, and the covering sheet 44,covering the surface of the first cushion member 41 with the seat skin40, and mounting the seat skin 40 on the seat skin mounting portion 47of the bottom plate 43 (see FIG. 9( d)). The vehicular seat 71 and thewatercraft seat 72 are made by the same making processes.

As described above, the method for making the vehicular seat 10according to the embodiment of the present invention includes the stepsof: forming the second cushion member 52; affixing the covering sheet 44generally to the second cushion member 52 excluding part thereof;setting the second cushion member 52, to which the covering sheet 44 isaffixed, onto the upper mold 81; loading the urethane material 83 intothe lower mold; closing the upper mold 81 and the lower mold 82; foamingthe urethane material 83 and integrally forming the first cushion member41 on the surface of the covering sheet 44 affixed to the second cushionmember 52; removing the integrated assembly of the first cushion member41, the second cushion member 52, and the covering sheet 44 from theupper mold 81 and the lower mold 82; and mounting the bottom plate 43 onthe lower surface of the integrated assembly of the first cushion member41, the second cushion member 52, and the covering sheet 44, coveringthe surface of the first cushion member 41 with the seat skin 40, andmounting the seat skin 40 on the bottom plate 43. The vehicular seat 10having the first and second cushion members 41, 52 integrated togethercan be easily obtained by foaming the urethane material 83.

Although the foregoing describes the exemplary preferred embodiments,various changes in form and detail may be made therein without departingfrom the spirit and scope of the invention.

For example, the vehicular seat according to the embodiments of thepresent invention are suited to those of motorcycles and saddle ridingtype vehicles and of automobiles and the watercraft seat according tothe embodiments of the present invention are suited to those of saddleriding type watercrafts. These are not the only possible applicationsand the present invention may be applied to seats in industrialvehicles, trains, aircraft, and other various types of vehicles.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

1. A vehicular seat comprising: a first cushion member formed ofurethane, the first cushion member being covered with a seat skin; asecond cushion member formed of a thermoplastic elastomer, the secondcushion member being disposed between the first cushion member and abottom plate; and a covering sheet disposed between the first cushionmember and the second cushion member.
 2. The vehicular seat according toclaim 1, wherein the covering sheet is disposed on the second cushionmember on a side thereof adjacent the first cushion member, and not onan entire surface or part of a side thereof adjacent the bottom plate.3. The vehicular seat according to claim 1, wherein the bottom plateincludes a rib disposed on an upper surface thereof, the rib extendingtoward a side of the second cushion member.
 4. The vehicular seataccording to claim 1, wherein the bottom plate includes a protrudingportion formed continuously at approximately a central portion of abottom of a recessed portion for supporting a lower surface of thesecond cushion member to enhance stiffness of the bottom plate.
 5. Thevehicular seat according to claim 1, wherein the bottom plate is formedof synthetic resin.
 6. The vehicular seat according to claim 1, whereinthe bottom plate includes a recessed portion formed at a central portionthereof for positioning the second cushion member.
 7. The vehicular seataccording to claim 1, wherein the bottom plate includes a seat skinmounting portion formed continuously on each outer portion of a curvedportion of the bottom plate.
 8. A watercraft seat comprising: a firstcushion member formed of urethane, the first cushion member beingcovered with a seat skin; a second cushion member formed of athermoplastic elastomer, the second cushion member being disposedbetween the first cushion member and a bottom plate; and a coveringsheet disposed between the first cushion member and the second cushionmember.
 9. The watercraft seat according to claim 8, wherein thecovering sheet is disposed on the second cushion member on a sideadjacent the first cushion member, and not on an entire surface or partof a side adjacent the bottom plate.
 10. The watercraft seat accordingto claim 8, wherein the bottom plate has a rib disposed on an uppersurface thereof, the rib extending toward a side of the second cushionmember.
 11. The watercraft seat according to claim 8, wherein the bottomplate includes a protruding portion formed continuously at approximatelya central portion of a bottom of a recessed portion for supporting alower surface of the second cushion member to enhance stiffness of thebottom plate.
 12. The watercraft seat according to claim 8, wherein thebottom plate is formed of synthetic resin.
 13. The watercraft seataccording to claim 8, wherein the bottom plate includes a recessedportion formed at a central portion thereof for positioning the secondcushion member.
 14. The watercraft seat according to claim 8, whereinthe bottom plate includes a seat skin mounting portion formedcontinuously on each outer portion of a curved portion of the bottomplate.
 15. A method for making a vehicular seat, the vehicular seatincluding a first cushion member formed of urethane, the first cushionmember being covered with a seat skin; a second cushion member formed ofa thermoplastic elastomer, the second cushion member being disposedbetween the first cushion member and a bottom plate; and a coveringsheet disposed between the first cushion member and the second cushionmember, the method comprising the steps of: forming the second cushionmember; affixing the covering sheet generally to the second cushionmember excluding part thereof; setting the second cushion member, towhich the covering sheet is affixed, into a first mold; loading aurethane material into a second mold; closing the first mold and thesecond mold; foaming the urethane material to thereby integrally formthe first cushion member on a surface of the covering sheet affixed tothe second cushion member; removing an integrated assembly of the firstcushion member, the second cushion member, and the covering sheet fromthe first mold and the second mold; and mounting the bottom plate on alower surface of the integrated assembly of the first cushion member,the second cushion member, and the covering sheet, covering a surface ofthe first cushion member with the seat skin, and mounting the seat skinon the bottom plate.
 16. The method for making a vehicular seataccording to claim 15, wherein the bottom plate includes a protrudingportion formed continuously at approximately a central portion of abottom of a recessed portion for supporting a lower surface of thesecond cushion member to enhance stiffness of the bottom plate.
 17. Themethod for making a vehicular seat according to claim 15, wherein thebottom plate includes a recessed portion formed at a central portionthereof for positioning the second cushion member.
 18. A method formaking a watercraft seat, the watercraft seat including a first cushionmember formed of urethane, the first cushion member being covered with aseat skin; a second cushion member formed of a thermoplastic elastomer,the second cushion member being disposed between the first cushionmember and a bottom plate; and a covering sheet disposed between thefirst cushion member and the second cushion member, the methodcomprising the steps of: forming the second cushion member; affixing thecovering sheet generally to the second cushion member excluding partthereof; setting the second cushion member, to which the covering sheetis affixed, into a first mold; loading a urethane material into a secondmold; closing the first mold and the second mold; foaming the urethanematerial to thereby integrally form the first cushion member on asurface of the covering sheet affixed to the second cushion member;removing an integrated assembly of the first cushion member, the secondcushion member, and the covering sheet from the first mold and thesecond mold; and mounting the bottom plate on a lower surface of theintegrated assembly of the first cushion member, the second cushionmember, and the covering sheet, covering a surface of the first cushionmember with the seat skin, and mounting the seat skin on the bottomplate.
 19. The method for making a watercraft seat according to claim18, wherein the bottom plate includes a protruding portion formedcontinuously at approximately a central portion of a bottom of arecessed portion for supporting a lower surface of the second cushionmember to enhance stiffness of the bottom plate.
 20. The method formaking a watercraft seat according to claim 18, wherein the bottom plateincludes a recessed portion formed at a central portion thereof forpositioning the second cushion member.